Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas, UNICAMP, P.O. BOX 52, Piracicaba, SP, 13414-903, Brazil.
B Chemistry Institute of São Carlos, University of São Paulo, São Carlos, SP, Brazil.
Odontology. 2024 Jul;112(3):729-738. doi: 10.1007/s10266-023-00875-0. Epub 2023 Dec 26.
To evaluate the bleaching efficacy and effects on enamel properties of experimental gels with carbamide peroxide (CP; 10%) or hydrogen peroxide (HP; 6%) containing calcium polyphosphate sub-microparticles (CaPPs).
A total of 216 bovine tooth specimens were divided for microhardness and color analyses (n = 108) and block randomized into nine groups (n = 12): (G1) commercial CP (Whiteness Perfect, FGM; Brazil); (G2) experimental CP; (G3) CP-0.5%CaPPs; (G4) CP-1.5%CaPPs; (G5) commercial HP (Potenza Bianco, PHS; Brazil); (G6) experimental HP; (G7) HP-0.5%CaPPs; (G8) HP-1.5%CaPPs; (G9) artificial saliva. The gels' pH values were determined with a bench pH meter. Color (ΔE, ΔE, ΔWI) and microhardness variation were evaluated before and after the therapy. Part of the specimens used for microhardness was submitted to the scanning electron microscopy (SEM) (n = 3) and energy-dispersive X-ray spectroscopy EDX (n = 3) analyses. Statistical analyses were performed in the R statistical software (α = 0.05). Linear mixed models for repeated measures in time were used to analyze microhardness and L* values. Generalized linear models were used to analyze the a*, b*, ΔE, ΔE, and ΔWI considering a group effect. The EDX data were analyzed using a one-way ANOVA with Tukey's test.
The gels' pH remained over 6,0. All gels effectively bleached the specimens and did not differ significantly. When compared to the control group, the hardness was significantly lower in the G1, G2, G6, and G7 groups. The G3, G4, G5, and G8 groups did not differ significantly (p > 0.05).
The incorporation of CaPPs in low-concentration whitening gels reduces its negative effects on microhardness without interfering with their bleaching efficacy.
评估含有过氧脲（CP；10%）或过氧化氢（HP；6%）的实验凝胶对牙齿漂白效果和釉质性能的影响，这些实验凝胶含有焦磷酸钙亚微米颗粒（CaPPs）。
共有 216 个牛牙标本被分为显微硬度和颜色分析（n=108）和块随机分为九组（n=12）：（G1）市售 CP（FGM 公司的 Whiteness Perfect，巴西）；（G2）实验 CP；（G3）CP-0.5%CaPPs；（G4）CP-1.5%CaPPs；（G5）市售 HP（PHS 公司的 Potenza Bianco，巴西）；（G6）实验 HP；（G7）HP-0.5%CaPPs；（G8）HP-1.5%CaPPs；（G9）人工唾液。使用台式 pH 计测定凝胶的 pH 值。治疗前后评估颜色（ΔE、ΔL*、ΔWI）和显微硬度的变化。一部分用于显微硬度分析的标本进行扫描电子显微镜（SEM）（n=3）和能量色散 X 射线光谱 EDX（n=3）分析。使用 R 统计软件进行统计分析（α=0.05）。使用时间重复测量的线性混合模型分析显微硬度和 L值。考虑组间效应，使用广义线性模型分析 a、b*、ΔE、ΔL*和 ΔWI 值。使用单向方差分析和 Tukey 检验分析 EDX 数据。
所有凝胶的 pH 值均保持在 6.0 以上。所有凝胶都能有效漂白标本，且差异无统计学意义。与对照组相比，G1、G2、G6 和 G7 组的硬度显著降低。G3、G4、G5 和 G8 组之间无显著差异（p＞0.05）。
在低浓度的美白凝胶中加入 CaPPs 可以降低其对显微硬度的负面影响，而不影响其漂白效果。
